Part are designed for 3d printing. It is best to use resin material, and some hand work is needed.To make it work well, the parts should be smooth enough.If you use PLA/ABS material,you need to try to make the part as smooth as possible.Some M2X8 （4pcs） and glue are needed to assemble the parts.Before using glue between parts bottom drive and top drive, you should try to test if the mechanism work well.The part bottom-there are two versions are included,you can print any one as needed. The part bottom drive-there are two versions too,I remove some material to reduce the weight on bottom drive-v2.You can just choose one version to print.When you drive the part bottom drive,the 4 blades open or close gradually. When it is open,the mouth diameter is 50mm.STL and STEP format files are included. Ignore the FBX and Obj format files,they are only for the platform requirement.